What is the name of the loops of wire that produce a magnetic field when current flows through them?

The loops of wire that produce a magnetic field when current flows through them are referred to as a solenoid. A solenoid typically consists of a long wire wound into a coil shape. When electric current passes through the wire, it generates a magnetic field, and if the coil is wrapped around a core (often made of ferromagnetic material), the magnetic field is significantly enhanced. This property makes solenoids useful in various applications, such as electromagnets, relays, and inductors.

Coils and inductors do produce magnetic fields and are related concepts, but the term "solenoid" specifically emphasizes the characteristics of the tightly wound loops or coils that create a uniform magnetic field inside. Inductors are often coils used in electronic circuits to store energy in a magnetic field, but they may not always be in the shape or configuration to be considered solenoids.